Planet Earth II02.docx

Planet Earth II02.docx

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PlanetEarthII02

Thereareonlyfourteenpeaksintheworldthatrisetoover8000meters.

Allofthemarehere,intheHimalayas.

Lethallycold,scouredbygalesandblizzards,thesemountainsareamongthemosthostileplacesonEarth.

Yet,afewspecialanimalsmanagetolivehere.

Snowleopards.

Likeallcreaturesofthehighmountains,theyhavehadtoadaptboththeirbodyandtheirbehaviourinordertosurvive.

Lifeatextremealtitudehasshapedsomeofthetoughestanimalsontheplanet.

Thesun-bakedmountainsoftheArabianPeninsula.

TheymayonlybeafractionoftheheightoftheHimalayas,buttheyarestillsodizzyinglysteepthatinmanyplacesit'salmostimpossibletogetafoothold.

YetNubianibexhavemadethistheirhome.

Theibexchoosethesteepestcliffstoraisetheiryoung,insafety,beyondthereachofpredators.

Butlivinginthissanctuarycomeswithacost.

Thesenurseryslopesaresosteep,thereisalmostnostandingwateruphere.

Sotodrink,anibexfamilymustdescendintothevalley...1,000feetbelow.

Themotherspickoutthesafestwaydown.

Withsoftclovenhoovesthatgripbetterthananyclimbingshoe,theyarethemostaccomplishedmountaineers.

Butthenewbornkidsarestillhavingtofindtheirfeet.

Thisistheirfirstdescent.

Onemistakecouldmakeittheirlast.

Followingtheadults,thekidsfinallyreachthevalley.

Butonceonlevelground,they'revulnerable.

Redfoxeslieinwait.

Atthefirstsignofdanger,theyoungibexinstinctivelyrunbacktosteeperground.

Butheadingforthisparticularrockyoutcropcouldbeamistake.

It'sa30-footdrop.

Thefoxhasthemtrapped...orsoitseems.

Thisiswhatibexwereborntodo.

Scatteringmakesithardforthefoxtopickatarget.

Anditcertainlycan'tfollowthemuphere.

Allitcandoiswaitforonetoslipandfall.

Buttheseyoungstersarefastlearners,andthey'renowalmostassure-footedastheirparents.

Thefoxwillhavetofinditsmealelsewhere.

It'sjustnotbeenagoodday.

Now,atlast,theyoungibexcandrink.

Butthey'llsoonneedtoreturntothesafetyofthesheercliffs.

Masteringprecipitousterrainisalwayschallenging,buttherearemorefundamentalproblemsforlifeinthemountains.

TheAlps.Europe'shighestpeaks.

It'swinter,andfoodisdesperatelyshort.

Agoldeneaglehastospendeverydaylighthourscanningtheslopesforsomething,somewhere,toeat.

Herseven-footwingspanallowshertoglideeffortlesslyfor100milesinasingleday.

Herextraordinaryeyesenablehertospotpreyfromtwomilesaway.

Butsheisnottheonlyonewho'slookingforfood.

Whenshespotsachance,shemustmovefast.

Shecandiveat200milesanhour.

Onlyaperegrineisfaster.

Duringwinter,eveneaglesrelyalmostentirelyoncarrion.

It'sadeadfox,anditcouldsustainherfordays.

Otherscavengersmustdefer.

Thehungrycrowssoonregaintheircourage.

They'lltryanytricktostealamorsel.

Andtheyareannoyinglypersistent.

Butthismobaretheleastofherworries.

Abiggereagletakescontrol.

Butthiskillistooimportanttogiveup.

Soshemustfight.

Forthemoment,she'swonthecarcassback.

Butakilllikethiswillattracteveryeagleformilesaround.

Asever,thestrongestwinsthelion'sshare.

Unabletodefendthecarcassanylonger,thefirsteaglemustnowcontinueitssearch.

Itmaybemanydaysbeforeshefeedsagain.

Onlythemostcompetitivewillsurvivetheperilsofthemountainwinter.

Anavalanche.

100,000tonnesofsnowtravellingat80milesanhour,capableofsmashingeverythinginitspath.

ThemountainsofNorthAmericaarehitbythousandsofavalancheseveryyear.

Yetoneanimalspendsthewholewinterslumberingwithinthesnowontheseavalanche-proneslopes.

Andwhenspringcomes,theyemerge.

Allacrossthesemountains,grizzlybearsmaketheirwinterdens10,000feetupinthedeepsnowofleewardslopes.

Andwhiletheywerehalf-asleepinthedepthsofwinter,theiryoungwereborn.

Nowthesecubsaretakingtheirfirststepsintotheoutsideworld.

Thismotherisleadingherthreeyoungsterstoaplacewheretheycanfindfood.

Theyneedtodescendasquicklyaspossible.

Thedebrisfromanavalancheisclearevidencethatthisslopeisstilldangerouslyunstable.

Thisisnotaplacetodawdle.

Andtheyhaveanotherreasontokeepmoving.

Afterfivemonthsintheden,thesebearsareveryhungry.

Bearsthathavehibernatedthroughoutthesepeaksnowalldescendtothevalleys,wherespringcomesearliest.

IntheRockies,seasonalchangeisswiftanddramatic.

Injustafewdays,theslopesturnfromwhitetogreen.

Meadowsthatonlyafewweeksagowereburiedbeneaththesnowarenowfulloflife.

Butinthesemountains,thegoodtimeswillnotlastlong.

Sothebearsmustfeedasfastastheycan.

Duringthesummermonths,anadultcanputon180kilosgorgingonplantsand,iftheycancatchthem...amarmotortwo.

Butjustnow,thebearshavesomethingelseontheirminds.

It'sbecomingwarmer,andthebearsarekeentoshedtheirthickwintercoats.

Mothersshowthecubswhattodoaboutthis.

They'llsooncatchon.

Sometrees,itseems,areparticularlysuitableforrubbing.

Bearshavetheirfavouritesandwilltravellongdistancestovisitthem.

Someitchesjusthavetobescratched.

Therearenowaround30bearsinthisonevalley.

Astheyrub,eachleavesanindividualandrecognizablescent.

Sothetreesooncarriesalistofwho'saround,whichmighthelpindividualstoavoidafight.

Tobestspreadtheirscent,theyreallyhavetoputtheirbackintoit.

Butsummerisshort.

Itchessatisfactorilyscratched,it'stimetoeat.

Inacoupleofmonths,theywillhavetoreturntotheirdenstohibernate,sonowtheymustputonasmuchweightastheycan.

Winterinthemountainsreturnsfastandhitshard.

TemperaturesintheRockieswilldropto-54degrees,socoldthatmoistureintheairfreezesintotinycrystalscalleddiamonddust.

Thisbobcatisoneofthefewhunterstoremainactiveinwinter.

Mostofhispreyisnowhiddenbeneaththesnowthatcovershisentireterritory.

Hehuntsbylisteningforthefaintestsoundofmovement.

Andtopreventcrunchingfootstepsfromrevealinghispresence,heusesbouldersassteppingstones.

Amouse.

Butoneisnotenough.

Thedeeperthesnow,theharderitistodetectprey,andtherewardsfortheeffortcanbedisappointing.

Tosaytheleast.

Bymidwinter,thesnowissodeepthatbobcatsareforcedtoleavetheirterritoriestotryandfindeasierhunting.

Andthisbobcatmaybeinluck.

Forthisparticularvalleyisblessed.

Ariverhereneverfreezes.

It'sfedbyavolcanichotspringthatheatsthesewatersto50degreeswarmerthanthesurroundingair.

Hungryanimalsofallkindscomeheretofeed.

Throughoutthewinter,theriverisfulloffoodforthosewhoknowhowtocatchit.

Here,eventhecoyoteshavebecomefishermen.

Buthuntingishardforacatthat'snotusedtogettingitsfeetwet.

Sohemustchoosehistargetwithcare.

Golden-eyeducks.

Butcanhegetcloseenoughtopounce?

Perhapshe'llhavemoreluckontheotherside.

Here,steamfromtheriverwarmsthesurroundingtrees,soupinthebranches,therecouldbeprey.

Ifonlyhecouldgettoit.

It's20feetup.

Atlast...asquirrel.

Notmuch,butenoughtokeephimgoing.

Tosurviveawinterinthesemountainstakestenacity,andbobcatshavethatinabundance.

Theyallthriveinthetropicalsun.

Afterall,everydayissummer.

Butoncethesunsets,everynightbecomesasbitterlycoldaswinter.

Snowontheequator.

UnliketheRockies,inthesemountainstherearenomarkedseasons.

ThisisAfrica'sMountKenya.

It's17,000feethigh,whichmakesitssummitsome30degreescolderthanthesurroundingsavanna.

Giantheathers,lobeliasandgroundselgrowonitsupperslopes.

Thetemperaturedropstofivedegreesbelowfreezing,turningthemountainsideintoagardenofice.

Everythingfreezes,butthecabbagegroundselshaveawayofprotectingthemselves.

Theycloseuptheirleatheryleavestoformaninsulatingblanketthatshieldstheirvulnerablecentralbud.

Nightcomestoanend...andthesunshinereturns.

Thegroundselsspreadtheirleaveswidetobaskinthesunshineonceagain.

DawnintheHighAndes.

Heretoo,therisingsunbringsrapidrelieftoanimalslivingamongstthesevolcanicpeaks.

Mountainviscachaareupearlytoclaimthebestplacestocatchthesun'sfirstrays.

Forothersuphere,thesunriseisevenmorewelcome.

Atover14,000feet,thisisthehighestflamingocolonyintheworld.

Atnight,itgetssocoldthateventhissaltywaterfreezesover.

Andnowtheflamingosaretrappedintheice.

Eventually,thesunthinstheice,butit'sstillastrugglefortheflamingostobreakfree.

Walkingonthiniceisalwaysrisky.

Andit'shardtoretainone'sdignity...especiallywhenyou'rewearingstilts.

Atthesealtitudes,thesun'spowercanquicklyturnfromsalvationtothreat.

Theatmosphereissothin,thereisverylittleprotectionfromultravioletradiation.

Bymid-morning,it'sriskytolingeroutintheopen.

Theviscachaareforcedtoheadfortheshade.

Outonthelake,thereisnowheretohide.

Thewhitecrustofthesodalakereflectsthesun'sglareandincreasestheimpactofitsultravioletrays.

Bymidday,uncoveredhumanskinwillburninfourminutes.

Butthisdoesn'tseemtobothertheflamingos.

Infact,theyareonparade.

Duringthebreedingseason,theflamingosperformthesepeculiarcourtshipdanceseventhroughthehottesttimeoftheday.

Theyaresoeager,theydon'tevenpausetofeed.

Therulesaresomethingofamysterybut,afteramonth